Except for the Pituitary Gland, all are broadly considered to be part of the Limbic System, receiving signals from Neurons that either secrete Serotonin or NorEpinephrine or from Neurons that secrete both NeuroTransmitters.
Reductions in the activity of circuits that use Serotonin and NorEpinephrine contribute to Depression in many people. Some Serotonin pathways (arrows) are indicated.
NorEpinephrine producing cells project from the Locus Coeruleus.